Fuel Injection Pump adjustment procedure (Bosch PES 6 KL 70 B 120 R20Y) USA 1969

[Peter]

I’m looking for the Fuel Injection Pump adjustment procedure (Bosch PES 6 KL 70 B 120 R20Y) USA 1969.
    1.   Standard adjustment mm-shims Altitude Compensator (I think it’s 2 mm)
    2.   Standard adjustment mm-shims Warm Running Device (I think it’s 0,70 mm)
    3.   CO-RPM levels and order of adjustment:
            a.   full load point – CO level – RPM
            b.   lower partial load range – CO level – RPM
            c.   Idle Speed Adjustment – CO level – RPM
            4.   Other adjustments?

Pls don’t forward the link to the technical manual as this procedure is not described there and yes the linkage of my car is good.

Thanks and kind regards, Peter

[mrfatboy]

Every pump is different. Your #1 and #2 are good starting points. You will just have to see what you pump best preforms at.

#3 is in the tech manual. You can also search for it 🤣


Idle       
750-800   RPM CO  3.5 - 4.5  =  AFR 12.80 - 13.20

Lower partial   
1500      RPM CO  1.5 - 3.0  =  AFR  13.40 - 13.95
3000+  RPM CO  0.2 - 1.5  =  AFR  13.95 - 14.50

Full load   
3000+  RPM CO  2.0 - 4.0  =  AFR  12.85 - 13.20



Although it’s not a step by step guide check out the FIPi simulator in the tech manual to get an understanding what all the adjustments do on the FIP.

[Shvegel]

The adjustments requiring shims are done by measuring things internal to the pump.  They are not a set thickness but rather the thickness of shim needed to reach a certain internal measurement within the governor.  The fuel mixture is set on an injection flow bench using volume of fuel delivered at a number of set RPM's and throttle openings.  for example 22ml of fuel per 1000 revolutions at 1600 pump RPM (half engine speed) and 60 degrees of throttle opening.  The unfortunate part is the test sheets with the data are very tightly held and are very hard to find.

[Peter]

My FIP has been overhauled.

I assume the internal settings are ok.

Is it possible to finetune now via the (external) shims and the Idle, Lower partial and Full load external adjustments de FIP when it is built on the engine?

If so, question is what is the order of adjustments?

Thanks, Peter

[mauro12]

Hello guys, I just overhauled my injection pump and I have chosen Hans Fritsczhe in Germany https://www.oldtimer-technik.eu.
He is very well reccomended by the pagoda club in Germany and also in this forum. The aspect that surprised me is that probably he is the only in the market to bench test the pump with a different method . In order to have the exact same quantity of fuel in each cylinder, he uses the frequency converter technology , to make it simple he is able to set your pump to almost the same ml or cm3 of fuel in each cylinder and that's critical for smooth engine and clean emissions. The old bench test have a residual margin of error and you can have slightly different ml of fuel per cylinder and that's no good for a perfect combustion. I wanted to share this with you.
My car is running perfectly now .
Thank you

Mauro

[Peter h]

That's what I meant by the right specialist company.
I and my pagoda friend have already had many pumps done there to our satisfaction. I and others have had bad experiences before. Of course, the rest of the engine must also be adjusted well so that a great result comes out. No problems with hot and cold starts and also with the warm-up phase, and less than 12 l per 100 km.
Peter

[garymand]

Hi Peter, I have a 250 with a 69 280 motor, I've owned since 1971.  I have adjusted the pump on the car with excellent, maybe surprising, results.  I started many years ago using the manual prescribed "tail sniffer" to measure CO2.  I didn't have much success.  Repeatability and accuracy were poor.  I got closer with a narrow band O2 meter with sensor in a tail pipe.  Finally I replaced it with a wide band meter and sensor. It is accurate and repeats.  (and a vacuum meter visible as you drive.) 

The big problem is the 280 pumps oil level is above the big access nut.  You loose 1/2 quart of oil each time you open the pump to adjust the Lower partial  and upper partial screws.   And of course, they effect each other as all 4 springs press on the same two counter balance weights.  Hopefully you have a reasonable bench adjustment to start with.   You also have the full load rack screw that is above the oil level.  But it also moves the governor settings richer or leaner. 

Yes they are interactive and take patience, comprehension, and many many circuits over the same "test track."  A few of my neighbors noticed and asked why I was driving around and around putting my breaks on for no seeable reason.   I live on a mile round circle with 2 hills that help releave the brakes as I try to maintain the vacuum at 1500 and 3000 RPM. 

I found it best to adjust the cold start and idle shims 1st. Then the governor 4 screws. Then check the shims again.  Once you get all that for highest power (which for my car was a bit rich), You can now use the rack for wide open throttle, which again can move the governor band rich or lean, but now you are really close and readjusting the governor and shims will require small adjustment.  And I found if I wanted highest performance or a bit of gas economy, I can just adjust the rack a few clicks without dumping 1/2 quart of oil. 

My pump had been setup very rich causing an extensive iterative process and many quarts of oil, but once I found the sweet spot, the performance felt 15 to 20% improved. 
I also pressure tested my injectors and found at about 100K miles the injectors were fine! 

The result is a big smile on my face as I'm driving fun roads.